Southwest® flights from St. Louis to Washington, D.C. (Dulles) from $129

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Low fares from St. Louis to Washington, D.C. (Dulles)

$

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 05/13/2026

One-way

Basic

From
$129
Seen: 2 hrs ago

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 04/28/2026

One-way

Basic

From
$129
Seen: 7 hrs ago

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 05/12/2026

One-way

Basic

From
$129
Seen: 2 hrs ago

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 05/05/2026

One-way

Basic

From
$129
Seen: 2 hrs ago

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 04/20/2026

One-way

Basic

From
$146
Seen: 9 hrs ago

St. Louis (STL)to

Washington, D.C. (Dulles) (IAD)
Depart: 06/01/2026

One-way

Basic

From
$156
Seen: 21 hrs ago

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Explore flights from St. Louis to Washington, D.C. (Dulles)

Mar 2026
From$255*
Seen: 8 hrs ago
One Way/Basic
Apr 2026
From$129*
Seen: 7 hrs ago
One Way/Basic
May 2026
From$129*
Seen: 2 hrs ago
One Way/Basic
$196
$481
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    • Range$196-$481

    *Fares displayed have been collected within the last 24 hours and may no longer be available at time of booking. Additional fees and charges for optional products and services may apply. Modifying this information may result in a different fare. To find the most updated fare, please visit Southwest.com. Fares listed are Basic, which are subject to additional terms and conditions.

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